Labelling machines are known, especially of the kind that use a label reel from which labels are cut and applied onto articles, in particular articles filled with a pourable food product.
The above-identified machines, known as roll fed labelling machines, substantially comprise a carousel for advancing the articles along a path, and a labelling unit which applies a plurality of labels onto relative articles along the path.
In detail, the labelling unit comprises:                at least one motorized feeding roll for moving a strip of label from a label reel towards the carousel;        a cutting unit for cutting a label of a given length from the label strip; and        a vacuum suction drum which receives the cut labels and transfers the labels to the articles in the carousel.        
Cutting unit comprises a rotary blade assembly and a stationary blade assembly which are positioned adjacent to the vacuum suction drum.
More precisely, rotary blade comprises a rotating drum and one or more cutting edges arranged at an outer periphery of the rotating drum.
Stationary blade assembly comprises a support and a blade which projects outwards from the support.
The label strip is taken at its free end by suction by the vacuum drum, and passes between the stationary and the rotary blade of the cutting unit.
More precisely, since the vacuum drum rotates an higher speed than the label strip speed, the vacuum drum pulls an end of the label strip.
The label strip thus passes within a passage which is defined by the rotary and stationary blades. When the rotary and stationary blades face each other, a label is cut and separated by the vacuum drum from the remaining part of the label strip.
Stationary blade is generally pentagonal or triangular in section and comprises only one cutting edge.
Furthermore, stationary blade is generally made in a softer material than the rotary blade.
The rotary blades are commonly square with multiple useable edges.
Furthermore, the rotary blades are commonly made of a harder material such as carbide to resist wearing from the label sliding across the cutting edge.
Accordingly, the stationary blade needs to be changed more often than the rotary blade.
A need is felt within the industry to reduce the time and the costs connected with the stationary blade replacement, so as to increase the throughput of the labelling machine.